"Windows is indeed slower than other operating systems in many scenarios, and the gap is worsening." That's one way to start an insider explanation of why Windows' performance isn't up to snuff. Written by someone who actually contributes code to the Windows NT kernel, the comment on Hacker News, later deleted but reposted with permission on Marc Bevand's blog, paints a very dreary picture of the state of Windows development. The root issue? Think of how Linux is developed, and you'll know the answer.

On the other hand once a driver lands into the kernel, it becomes the same moving target as the whole thing. Most of the webcams released for Windows XP no longer work on Windows Vista/7/8 while in Linux you can use many of those webcams on all kinds of hardware, from laughingly old x86 to boards such as Rasberry PI. Plug it in and it just works! Thank you Linus, this is the reason why I love Linux. It might be beneficial in few cases to have a stable ABI but see the bigger picture and imagine today's stuff that just works in 20 years time - unlike Windows. I think having stable ABI would prevent it.

Webcams are a telling example, but not necessarily in the way you think... I'm sort of a collector of old webcams (I even have the very first dedicated webcam, Connectix Quickcam for ADB Macintoshes) and it's not so well under Linux.

Model/family-specific Linux drivers for oldish webcams are often quite half-baked, not exposing all the functionality, full capability of the camera. Just because a driver is in the kernel, doesn't mean it can't be neglected...

MS pushed through USB video class (as a Windows logo requirement), which also did improve the situation on Linux - and still the driver is somewhat half-baked (since it's within v4l2, it doesn't support stills)

Plus, "Most of the webcams released for Windows XP no longer work on Windows Vista/7/8" is probably not true - especially big names often do released Vista & up drivers.